FeCrNiAlCu中间层铝/铜电阻点焊接头的组织性能

Microstructure and properties of aluminum/copper resistance spot welding joint with FeCrNiAlCu as intermediate layer

采用FeCrNiAlCu高熵合金粉末作为中间层,对2A16铝合金/T2紫铜进行电阻点焊,研究高熵合金粉末对接头显微组织和力学性能的影响。结果表明:高熵合金粉末与液态铝合金存在元素相互扩散现象,并且反应生成富Al的固溶体过渡层。铜侧界面存在两层相结构组织,分别为富Al的固溶体层以及由Al_(2)Cu化合物组成的金属间化合物层(Intermetallic compound,IMC),部分固溶体颗粒与母材形成机械咬合。在焊接电流大小为20~32 kA时,接头的拉伸强度随焊接电流的增加先增加后减小;电流大小为25 kA时,接头的拉伸强度最高,达到1.64 kN,较无中间层的接头提升了30%;接头的断裂发生在铜侧界面处。

Using FeCrNiAlCu high entropy alloy powder as the intermediate layer,resistance spot welding was carried out on 2A16 aluminum alloy/T2 red copper.The effect of high entropy alloy powder on microstructure and mechanical properties of the joint was studied.The results show that there is an element mutual diffusion phenomenon between high entropy alloy powder and liquid aluminum alloy,and the Al-rich solution transition layer is formed.There are two layers of phase structure at the copper side interface,which are Al-rich solution layer and the IMC(Intermetallic compound)layer composed of Al_(2)Cu compound.Some solution particles form mechanical occlusion with the base metal.When the welding current is 20-32 kA,the tensile strength of the joint first increases and then decreases with the increase of welding current.When the current is 25 kA,the tensile strength of the joint is the highest,reaching 1.64 kN,which is 30% higher than that of the joint without an intermediate layer.The fracture of the joint occurs at the copper side interface.